R5550K Series

Pch Load Switch IC with Current Sense and Voltage Sense

The R5550K Series are CMOS-based load switch ICs. Pch Tr. is used to achieve low On resistance (TYP.180mΩ) and low supply current (TYP. 2.6µA at no-load operation). Internally, a single IC consists of a voltage reference unit, an error amplifier, resistors for setting output voltage and a current limit circuit. Output voltage is fixed inside the IC with high accuracy. The R5550K is suitable for monitoring abnormal current which may flow from lithium ion battery (one cell) to power lines connected to each load. If the abnormal current is detected, the switch turns off after a certain period of time (Dead-time).
The R5550K includes two types of switching operation after the turned-off period: automatic recovery type and latch type (UD*1). If overcurrent is detected, switch turns off after dead-time of 10ms. If the output current exceeds the output current limit, the output current limit circuit immediately controls the output current after the short current response time of 4µs. Then, switch turns off after dead-time of 1.33ms.
The R5550K also includes a voltage sense pin which monitors abnormal voltage. If abnormal voltage is detected, switch turns off after dead-time of 10ms. The R5550K includes a voltage sense pin (R5550KxxxA/ R5550KxxxE (UD)), an external capacitor connecting pin for setting protection delay time (R5550KxxxG (UD)) and a chip enable pin (R5550KxxxH (UD)).
As protection circuits, the R5550K contains an output current limit circuit, a short-current protection circuit, and an undervoltage lockout (UVLO) circuit.
The R5550K is available in a DFN(PLP)1010-4F package which enables the high-density mounting.
*1 Product Status: UD (Under Development), TBD (To Be Determined)